/Engine/Source/Editor/BlueprintGraph/Classes/K2Node.h
Handle when a variable is renamed in the Blueprint Palette
virtual void HandleVariableRenamed ( [UBlueprint](API\Runtime\Engine\Engine\UBlueprint) * InBlueprint, [UClass](API\Runtime\CoreUObject\UObject\UClass) * InVariableClass, [UEdGraph](API\Runtime\Engine\EdGraph\UEdGraph) * InGraph, const [FName](API\Runtime\Core\UObject\FName) & InOldVarName, const [FName](API\Runtime\Core\UObject\FName) & InNewVarName )